In 1959's Flash #105, The Master of Mirrors, Mirror Master made his triumphant debut. Since that time, a number of villains have donned the trademark orange and green in an attempt to topple the Flash. While Flash's most famous foes are probably Gorilla Grodd and Captain Cold, Mirror Master is right up there as a member of the Rogues and notorious enough to earn him a spot as Flash's primary challenger in the upcoming Justice League: Doom.
Mirror Master made his onscreen debut on 1984's Super Friends: The Legendary Super Powers Show even in the absence of Flash. As a child this episode gave me the incorrect notion that the 6th dimension was the dimension inside mirrors. My high school Geometry teacher begged to differ.
The original Mirror Master, Sam Scudder appeared in an episode of the live action Flash TV series. Although he wore a greenish suit, he differed quite a bit from his comic counterpart, using holograms rather than mirrors to commit crimes.
In the Justice League animated series episode Eclipsed, Mirror Master made a brief cameo during a in episode commercial for the fictional product Lightspeed Energy Bars, for which Flash had an endorsement. It should be noted that this MM was not really the villain, just an actor playing the part got the commercial.
On Justice League Unlimited, the actual Mirror Master appeared along with his fellow Rogues in the Flash tribute episode Flash and Substance.
On The Batman Animated series, Mirror Master appeared with a female sidekick Smoke. The cleverly named duo "Smoke and Mirror" Master both wore orange and green, though MM let the top down so his hair could blow in the wind.
In Batman: The Brave and the Bold's Four Star Spectacular, Mirror Master was featured in one of the episodes four shorts. The Flash in Double Jeopardy offered a showdown between the Scarlet Speedster and the Master of Mirrors along with another longtime Flash foe, Abra Kadabra.
Up next, the Mirror Master will join the Legion of Doom in Justice League: Doom. From the trailer, it appears as if MM may be second in command after the scandalous Vandal Savage.